The scientific motivation, design criteria, and specifications for a new ground-based instrument to observe the Sun in the He i 1083-nm spectral line is described. The instrument employs a liquid-crystal tunable Lyot-type spectral filter and an array detector that allows the full solar disk to be observed with a time cadence of minutes. We describe the telescope’s optical and mechanical features and discuss computer interface and data-reduction procedures employed. Instrument performance during the initial year of operation of the telescope at its high-altitude site is summarized.
© 1998 Optical Society of America
Original Manuscript: December 15, 1997
Revised Manuscript: March 16, 1998
Published: July 1, 1998
David F. Elmore, Gregory L. Card, Clarke W. Chambellan, Donald M. Hassler, Howard L. Hull, Alice R. Lecinski, Robert M. MacQueen, Kim V. Streander, John L. Streete, and Oran R. White, "Chromospheric helium imaging photometer (an instrument for high time cadence 1083-nm wavelength solar observations)," Appl. Opt. 37, 4270-4276 (1998)